## 1. Project Objectives

**Main objective:** To reduce nanoparticles pollution in the environment.

**The general interdisciplinary objectives of the project are**:

- Mathematical modelling and numerical simulation of the behaviour of nanometric particle suspensions in fluid compressible environment – combustion gases – under the action of an electric field for describing nanoparticles capture,

- Experimental modelling and optimization of filtering processes, in order to reduce the nanoparticles emissions in the combustion gases,

- Development of a pre-feasibility study of the suggested product both from an economic perspective and in terms of an intervention through public policy, in order to estimate the intention of investing in nanometric particle filters.

**Operational objectives and estimated results:**

**O1: The build-up of a data basis containing the main theoretical and experimental results published in the field**

Documentation and classification of the bibliography based on specific criteria: theoretical, computational, experimental, nanoparticles analysis and characterization

**O2: Mathematical modelling of the behaviour of nanometric particle suspensions in compressible fluid under the action of an electric no uniform field**

**2.1 Identification of the system of equations which governs the system dynamics, the computational domain, the specific initial and boundary conditions**

All forces acting upon the suspension particles (viscous resistance force, gravitational force, Archimedes force, Brownian force, Van der Waals force) will be identified and the equations that govern the particle movement under these forces will be written. The movement equations will be solved in a suitable computational domain, under specific boundary and initial conditions.

**2.2 Determining the values of the parameters involved in the system**

For a realistic description of the system, the numerical values of the material or geometric parameters involved in the equation system must be known. Their value will be determined using data taken from literature.

**O3: Numerical implementation of the mathematical model**

**3.1 Developing the programme for simulating the nanoparticles dynamics in AC electric fields**

The movement equations will be solved in a suitable computational domain, by introducing the value of the material parameters as well as the specific boundary and initial conditions. The numerical calculations will be performed with ANSYS Multiphysics, competitive specialized software using the finite element method.

**3.2 Validating the developed programme by comparing the obtained results to the results published in the specific literature**

The programme will be validated by comparing it to results published in the literature on geometry or problems that are less complex than the studied one. The number of nodes in the computational domain and the time step required for numerically correct solutions will be determined. Following this stage, the more complex problem studied as part of this project can be solved.

**O4: Numerical simulation of the behaviour of nanoparticles suspensions in combustion gases, under the action of an electric field for particle capture**

The great advantage of using numerical simulations in describing complex systems is that they allow the testing of the behaviour after a large number of parameters have been changed; the testing procedure is performed at low costs and in a relatively short time.

**4.1 Studying the influence of particle characteristics and fluid environment**

The dimension of the suspension particles is a parameter that has a major influence on the forces that act in the system. Based on the numerical simulations, one can determine the trajectories of the particles of different sizes under the action of the electric field applied with various electrodes. In addition, by changing some programme parameters, numerical simulations allow the investigation of the role played by the physical properties of the particles, combustion gases temperature and velocity.

**4.2 Determining the system parameters to develop an optimal nanoparticles capturing process**

Starting from the studies mentioned at 4.1 and based on a systematic analysis, one can determine the set of geometrical (electrode shape and place, particle size) and physical-chemical parameters that lead to an optimal nanoparticles capture process.

**O5: Experimental modelling of nanoparticles capture process within the combustion gases emissions in a non-uniform electric field based on simulations results.**

**5.1 Designing, building and testing an experimental device for capturing particles from the combustion gases in an electric field**

Based on the results obtained during the simulations specified at **O4**, in co-operation with ProAirClean, a waste incineration company in Timişoara, we will design, building and testing an experimental filter for capturing of nanometric from the combustion gases particles in a non-uniform alternating electric field.

**5.2 The collecting of the nanometric particles**

By using the experimental device, the nanometric particles exhausted by incinerator of ProAirClean Timisoara will be retained and separately collected.

**O6: The analysis of the collected nanometric particles**

The particles collected with the experimental device will be analyzed and characterized. The study will be focused on quantities, size classes and composition. A comparison of the obtained results with data from literature will be performed.

**O7: ****Establishing of efficient regimes in nanoparticles manipulations using the ****“Design of experiments” method.**

A feedback will be created that will lead to improved mathematical methods, best possible experimental methods and optimal parameters of nanoparticles capture processes.

**7.1 The improvement of the mathematical model **

**7.2 The optimization of the experimental device geometry**

** 7.3 The optimization of the physical and chemical parameters of the separation process (the voltage applied on the electrodes, the frequency, the fluid medium characteristics).**

**O8: ****Substantiation**** of**** a model of public environmental policy and strategies meant to reduce nanoparticles emissions in the city of Timisoara. The identification of the utility domains and of the potential users**

**8.1 Estimating the range of nanoparticles emissions in Timisoara**

The economic agents whose production processes generate nanoparticles emissions will be identified. A map of the nanoparticles pollution in Timişoara will be drawn with the help of systematic measurements of the nanoparticles air level in key points.

**8.2 Proposing an intervention model for the reduction of nanoparticles emissions in Timisoara**

Examples of successful intervention policies in the European Union member states will be studied. Based on them, a paper describing the desirable situation will be drawn up. Round tables with the local decision-making authorities will be organized to inform them about the results of the project and to know their position regarding the nanoparticles emissions issue. Workshops will be organized and visits will take place to economic agents generating polluting emissions, in order to estimate their intention to invest in nanometric particle filters.